drivers/base: base.h: add proper copyright and header info

base.h didn't have any copyright information in it, so update it with
the correct information.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20191209193303.1694546-2-gregkh@linuxfoundation.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>